ho da wagon

iTrader: (1)

my car has a VF 30 Turbo, and my check engine light came on and my accessport was telling me that it was cylinder 4 misfire..

then the next day, it said that cylinder 2,3,4 misfired..what are the cause's of misfire..could it be spark plugs?, my car is a 2003 and has about 14,xxx miles.

the ecu's base map is set to economy, should the base map be set to VF 30 because of the upgraded turbo..lmk..thanks.

kolohe_04sti

iTrader: (20)

do you have AP1 or 2? what are your mods? p304 or cyl 4 misfire could be caused by a lot of things but is a common cel. when does the cel come out? try posting this on cobb forums also. they normally respond quickly.

thunder_sti

iTrader: (5)

Here are some info. Hopefully it works out.

P0304 Code - Cylinder #4 Misfire

Technical DescriptionCylinder #4 Misfire Detected

What does that mean?

A P0304 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #4.

SymptomsSymptoms may include:

the engine may be harder to start
the engine may stumble / stumble, and/or hesitate
other symptoms may also be present

CausesA code P0304 may mean that one or more of the following has happened:

Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Running out of fuel
Poor compression
Defective computer

Possible SolutionsIf

there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

thunder_sti

iTrader: (5)

Check this one code out!!

P0300 Code - Cylinder Misfire

Technical DescriptionRandom/Multiple Cylinder Misfire Detected

What does that mean?

Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly.

A P0300 OBD code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.

SymptomsSymptoms may include:

the engine may be harder to start
the engine may stumble / stumble, and/or hesitate
other symptoms may also be present

CausesA code P0300 may mean that one or more of the following has happened:

Faulty spark plugs or wires
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector(s)
Burned exhaust valve
Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages
Faulty camshaft position sensor
Defective computer

Possible SolutionsIf

there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

VRT MBasile

iTrader: (17)

I dont think the economy map should be used as a basemap, I'd reflash to the correct map for that turbo

ho da wagon

iTrader: (1)

thank you everyone for your help..i am going to look into what you guys suggested..thanks.

the cel has not come back on ..so i am not to sure right now..but i will keep you guys posted if anything appears again..and i am going to reflash the ecu.
thanks again.

and its accessport ver.1